Biceps Brachii   

- Anatomy:

    - origin:
            - long head:  supraglenoid tuberosity of the scapula
            - short head: apex of coracoid process of scapula;
    - synergists: brachialis, brachioradialis, supinator;
    - innervation: musculocutaneous, C5  > C6;
    - insertion:
             - bicipital tuberosity of the radius and lacertus fibrosis; 
             - inserts on ulnar side of the lesser tuberosity, rather than as a cylinder on the center of the tuberosity;
             - lacertus fibrosus typically originates from the distal short head of the biceps tendon
             - references:
                      - The anatomy of the bicipital tuberosity and distal biceps tendon. 
                      - Distal Biceps Tendon Anatomy: A Cadaveric Study. 


    - action:
             - flexes and supinates the forearm at the elbow;
             - reversed origin insertion action: both hands of biceps brachi are active during flexion of arm at shoulder joint, with the long head being more active;
    - long head of biceps: 
        - see: biceps tendonitis / tendonopathy / proximal biceps tendon rupture
        - attaches to the supraglenoid tubercle of glenoid & has stabilizing and depressing action on humeral head;
        - it can act as a tether and block closed reductions of proximal humerus;
        - it is a useful landmark from which the rotator interval can be identified so that bone fragments are properly identified & rotator cuff  are preserved;
        - references:
              - The role of the long head of the biceps brachii in superior stability of the glenohumeral joint.
              - The Transverse Humeral Ligament. A Separate Anatomical Structure or a Continuation of the Osseous Attachment of the Rotator Cuff? 
              - Subluxations and dislocations of the tendon of the long head of the biceps

- Pathologic Conditions:
    - biceps tendonitis / tendonopathy :
    - distal biceps tendon rupture:
    - proximal biceps tendon rupture:
    - erb's palsy :
         - persistent absence of biceps muscle function at age 6 months in pts w/ C5-6 brachial plexus palsy from birth has been shown to correlate
                  w/ a poor prognosis for functional recovery;
         - early brachial plexus exploration & nerve grafting will improve f(x) 

Traumatic closed transection of the biceps brachi in the military parachutist.

Rupture through the short head of the biceps muscle belly. A case report.

A technique for maximizing biceps recovery in brachial plexus reconstruction

Anatomy and Histology of the Transverse Humeral Ligament

Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Wednesday, October 16, 2013 1:34 pm